First published version, module and package headers, table of contents

### Renderer - Prepare for MavenCentral publication (!9) - Fix broken module page when module name contains spaces (!10) - Support module header description via 'includes' (!10) - Fix table of contents not appearing on any pages (!10) - Classes and top-level functions are displayed in each package's page (!10) ### Dokkatoo plugin - All pages are added to the MkDocs navigation (!7) - Prepare for MavenCentral publication (!9)